Vibration producing apparatus

ABSTRACT

A vibration producing apparatus comprising a frame, a cylindrical space formed in said frame, a fluid supply port communicating with said cylindrical space, a vibratory member mounted in said cylindrical space for angular rotation, and two shield projections disposed at positions diametrically opposed to each other on an outer peripheral surface of said vibratory member and extending in opposite directions into sliding engagement with an inner peripheral surface of said cylindrical space. A vibration producing apparatus further comprises means for causing one of said shield projections to be disposed on the fluid supply port side and precluding angular rotation of said vibratory member over and above a predetermined angle, and ports adapted to maintain communication with said cylindrical space outside the range of movement of the other shield projection of said vibratory member.

United States Patent 1 Maeda 3,759,283 [451 Sept. 18,1973

1 1 VIBRATION PRODUCING APPARATUS [76] Inventor: Teruyuki Maeda, 6-5,Kita-machi,

3-chome, Kichijoji, Musashino City, Tokyo, Japan [22] Filed: Nov. 29,1971 21 Appl. No.: 202,861

[30] Foreign Application Priority Data Sept. 10, 1971 Japan 46/69764Dec. 10, 1970 Japan 45/109891 [56] References Cited UNITED STATESPATENTS 264,975 9/1882 Nerden 91/339 212 9/ 2 Reynolds 91/ 3, ,250 12/ 9Toby 91/ Primary Examiner-Paul E. Maslousky Attorney-Davidson C. Milleret a1.

[57] ABSTRACT A vibration producing apparatus comprising a frame, acylindrical space formed in said frame, a fluid supply portcommunicating with said cylindrical ce, avibratory member mounted insaid cylindric pace for angular rotation, and two shield projectionsdisposed at positions diametrically opposed to each other on an outerperipheral surface of said vibratory member and extending in oppositedirections into sliding engagement with an inner peripheral surface ofsaid cylindrical space. A vibration producing apparatus furthercomprises means for causing one of said shield projections to bedisposed on the fluid supply port side and precluding angular rotationof said vibratory member over and above a predetermined angle, and portsadapted to maintain communication with said cylindrical space outsidethe range of movement of the other shield projection of said vibratorymember.

4 Claims, 3 Drawing Figures PATENTEU 86H 8 I975 SHEET 1 BF 2 FIG./

PAIENIED SHEET 2 UP 2 FIG.

VIBRATION PRODUCING APPARATUS This invention relates to a vibrationproducing apparatus which relies on hydraulic pressure for producingvibration.

Hitherto, there have been several types of vibration producing apparatusavailable for various purposes. In one type of mechanical vibrationproducing apparatus known in the art, an eccentric cam and otherelements are used. Such apparatus have disadvantages in that adjustmentsof amplitudes of vibrations are not possible, and the apparatus requirehigh mechanical rigidity and a large space for installation becausetheir size is considerably great. Besides, the apparatus do not lendthemselves to selectively causing any particular point to vibrate asrequired.

There are also electrically operated vibration producing apparatus. Suchapparatus are capable of producing vibration at high frequency but notcapable of developing a high output at a high amplitude. Vibrationproducing apparatus relying on internal combustion engines or pneumaticpressure devices give off large noises when exhausts are vented, therebymaking a public nuisance of themselves. Vibration producing apparatususing a servo-valve of the electrohydraulic systern are capable ofdeveloping a high output at high precision but high in cost. Suchapparatus are used only in laboratory and not fit for practical use.

This invention obviates the aforementioned disadvantages of thevibration producing apparatus of various types of the prior art.

Accordingly, this invention has as its object the provision of avibration producing apparatus of the fluid pressure type which causes avibratory member to vibrate in self-oscillation by hydraulic means.

Other and additional objects of the invention are those inherent in theinvention hereinafter shown, described and claimed and will becomeevident as the description proceeds.

in the drawings:

FIG. 1 is a vertical sectional view of the vibration producing apparatuscomprising one embodiment of this invention;

FIG. 2 is a sectional view taken along the line X-X of FIG. 1; and

FIG. 3 is a sectional view of the apparatus comprising anotherembodiment.

In FIG. l and FIG. 2, the numeral 1 designates a frame of the vibrationproducing apparatus A which is formed at one end thereof with acylindrical space 2 and a bearing housing recess 4 contiguous with eachother with an ofiset portion 3 being formed therebetween. A fluid supplyport 5 is formed at one side of an outer periphery of frame 1 tocommunicate with cylindrical space 2, and ports 6, 6a, 7, 7a, 8 and 8acommunicating with cylindrical space 2 are formed at a side of the outerperiphery of frame 1 which is opposite to the side at which fluid supplyport 5 is located. Ports 6, 6a, 7, 7a, 8 and 8a are disposedsymmetrically relative to each other with respect to a diametrical linepassing through the center of frame 1 and fluid supply port 5.

Throttle valves 9 and 9a are mounted midway in ports 6 and 6arespectively, and adjusting rods 10 and Ma are slidably mounted in ports7 and 70 respectively for movement into and out of cylindrical space 2.

The numeral iii designates a vibratory member comprising a discalportion 12 which is of a diameter greater than the diameter of bearinghousing recess 4 but smaller than the diameter of cylindrical space 2Discal portion 12 is formed, at positions on the outer periphery thereofwhichare diametrically opposed to each other, with shield projections 13and 14 maintained in sliding contact at their front ends with an innerperipheral surface of cylindrical space 2. Discal portion 12 is alsoformed with shafts H5 and 16 integral with discal portion 12 andprojecting upwardly and downwardly respectively.

The upper shaft i5 is rotatably journalled by a bearing l7 which isfitted in bearing recess 4. A cover 18 includes a columnar projection 19which is fitted in cylindrical space 2, and the lower shaft 16 ofvibratory member 11 is journalled by a bearing 22 which is fitted in abearing recess 20 formed in columnar projection 19.

The cylindrical space 2 of frame ll, the discal portion 12 of vibratorymember ll 1, the columnar projection 19 of cover 18, and the shieldprojections 13 and 14 of vibratory member 11 define therebetween leftand right arcuate spaces 22 and 23. Two stoppers 24 and 24a are attachedto one side of an upper surface of columnar projection 19 and disposedat the side opposite to the side of frame I at which fluid supply port 5is disposed. One shield projection 14 of vibratory member ll 1 isdisposed between two stoppers 24 and 24a.

The columnar projection 19 of cover 1% is formed with ducts 25 and 25amaintained in communication left and right arcuate recesses 22 and 23respectively.

B designates a fluid power amplifying apparatus provided with a frame 26formed with a cylindrical bore 27 receiving therein a spool valve 311formed with lands 29, 28 and 30 at a center and opposite ends thereofrespectively. Springs 32 and 33 are mounted on opposite ends of spoolvave 31, and cylindrical bore 27 is closed by a cover 34.

Spool valve 31 divides cylindrical bore 27 into a left chamber 35 and aright chamber 350 which are maintained in communication with the ducts25 and 25a formed at the arcuate spaces of vibration producing apparatusA through ducts a4 and 44a respectively which are formed in frame 26.Frame 26 is also formed therein with a fluid outlet duct 36 which isconnected to cylindrical bore'27 between the spool lands 28 and 30 atthe opposite ends of spool valve 31. A high pressure fluid supply duct37 connected at one end to a high pressure fluid source is connected atother end to the central portion of cylindrical bore 27. Bent ducts 38and 380 are formed in frame 26 and connected at one end to a portion ofcylindrical bore 27 between the spool lands 28 and 29, and 29 and 30 atthe opposite ends of spool valve 31.

C designates an output producing apparatus formed with a cylindricalbore 39 receiving therein a piston 40 supported by rods 41 and Maintegrally connected to opposite ends of piston 40 and extending out ofoutput producing apparatus C to serve as an output shaft. Apparatus C isformed therein with ducts 43 and 43a which maintain a left chamber 42and a right chamber 42a of cylindrical bore 39 divided by piston 4thwith the other end of bent ducts 38 and 380 formed in apparatus 8.

Operation of the vibration producing apparatus constructed asaforementioned will now be described. The fluid under pressure suppliedthrough fluid supply port 5 passes into right arcuate space 23 shown inFIG. 2

and is discharged through duct 8a. This flow of fluid under pressureacts on one shield projection 14 and moves the same clockwise in FIG. 2by the energy of the fluid, so that vibratory member lll angularlyrotates clockwise in FIG. 2 till shield projection 14 strikes againstone stopper 24 and is stopped thereby.

At this time, the other shield projection 13 of vibratory member llll isdisposed rightwardly of fluid supply port in FIG. 2, so that the fluidunder pressure introduced through port 5 into the apparatus A passesinto left arcuate space 2.2 in H6. 2 and is discharged through port 8.This flow of fluid under pressure acts on shield projector l4 and movesthe same counterclockwise in FIG. 2 by the energy of the fluid, so thatvibrator member ill angularly rotates counterclockwise in Fl'G. 2 tillshield projection 14 strikes against the other stopper 24a and isstopped thereby.

This process is repeated over and over again so that vibratory member ilmoves in vibratory motion.

The quantity of fluid under pressure introduced into left and rightarcuate spaces 22 and 23 can be adjusted by moving backwardly orforwardly adjusting rods lb and ltla or turning throttle valves 9 and 9aso as to set the number of vibrations of vibratory member til at anylevel as desired.

If fluid under pressure is supplied to the vibration producing apparatusA as aforesaid to cause the vibratory member if to vibrate, fluidpressure of left and right arcuate spaces 22 and 23 are appliedrespectively through ducts 25 and 25a to the cylindrical bore 27 of thefluid power amplifying apparatus B, so as to move spool valve 31 toright and left.

Fluid under high pressure is supplied through high pressure fluid supplyduct 37 to cylindrical bore 27 when spool valve 31 is moving to left andright as aforementioned. Thus, when a quantity of fluid under pres sureis supplied to the right arcuate space 23 of the vibration producingapparatus A and introduced into the right chamber 35a of the cylindricalbore 27 of the fluid power amplifying apparatus B so as to move spoolvalve 31 to left, a quantity of fluid under high pressure passes througha space in bore 27 between the spool lands 29 and 3b of spool valve 31and ducts 38a and @311 into the right chamber 42a of the cylindricalbore 39 of the output producing apparatus C, so that piston oh andpiston rods 41 and 41a move to left as a unit.

On the other hand, when a quantity of fluid under pressure is suppliedto the left arcuate space 23 of the vibration producing apparatus A andintroduced into the left chamber 35 of the cylindrical bore 27 of thefluid power amplifying apparatus B so as to move spool valve 31 to righta quantity of fluid under high pressure passes through a space in bore27 between the spool lands 23 and 29 of spool valve fill and ducts 3band 43 into the left chamber d2 of the cylindrical bore 39 of the outputproducing apparatus C, so that piston so and piston rods lll and dismove to right as a unit.

FIG. 3 shows a modified form of the vibration producing apparatus Aaccording to this invention. The apparatus of FlG. 3 is substantiallysimilar in construction to the apparatus shown in FIG. l and F16. 2.except for the fact that the former is provided with two fluid supplyports 5a and 5b connected to a cylindrical space formed in frame llinstead of the fluid supply port 5 of the latter which fluid supplyports 5a and 51'; may be of any shape as desired and disposed at anyangle 9 with each other. The provision of fluid supply ports $12 and Sbpermits vibratory member if to continuously move in self-oscillationwithout the aid of stoppers 2d and 2411. Combined with theaforementioned hydraulic pressure increasing apparatus 5 and the outputproducing apparatus C, the vibration producing apparatus formed withfluid supply ports as shown in Fit 3 can function in the same manner asthe apparatus shown in FIG. 3 and FIG. 2.

Operation of the apparatus shown in H6. 3 wil now be described. When aright end of one shield projection 13 of vibratory member illl passes onone fluid supply port 51; in its counterclockwise angular movement, thearea of the port 5b communicating with chamber 23 varies with time, sothat vibratory member it receives a supply of energy of vibration fromthe fluid (or subjected to negative damping in an academic term) andangularly rotates counter clockwise. if the right end of shieldprojection i3 is released from engagement with fluid supply port 5b bythe angular rotation of vibratory member ill, then no energy ofvibration is supplied to vibratory member ill because there is no changein the area of port Sb with time, so that vibratory member M is onlymoved by inertia. This movement of vibratory member ii is damped by thehydraulic pressure ap plied to shield projector 34 and the force ofviscous resistance exerted thereon, so that vibratory member ll stops ina position shown in FIG. 3. Since hydraulic pressure is applied to theshield projection 14 of vibratory member Ill now standing still,vibratory member llll is pushed back to move clockwise. This opens theother fluid supply port 5a, and the aforementioned process is repeated.As a result, the embodiment of the vibration producing apparatus A shownin FllG. 3 can function satisfactorily without using the stoppers.

In the embodiment shown in FIG. 3, two limiters dd and 4140 may beprovided on an upper surface of columnar projection T9 to projectupwardly therefrom so that one shield projector lid may be interposedbetween the two limiters 44 and 44a. The provision of such limiters iseffective to prevent vibratory member Ill from being disposed in anundesirable position when it stands still. The limiters 34 and dda arepositioned such that they are spaced apart from each other as much aspossible and yet they can prevent the two fluid supply ports fromcommunicating with each other through arcuate space 22 or 23.

Thus, the piston rods 4i and dla or output shaft of the output producingapparatus C will be caused to move in vibratory motion by high pressurefluid at the same number of vibrations as the vibratory member iii ofthe vibration producing apparatus A for operating a vibrating screen,vibratory feeder, vibratory pile-driver, vibratory tarnping machine andthe like.

From the foregoing description, it will be appreciated that thevibration producing apparatus according to this invention is simple inconstruction and yet capable of causing a vibratory member to vibrate inselfoscillation by a spring force of fluid. The apparatus can readilyvary the number of vibrations of the vibratory member by effectingadjustments of the flow rate of fluid. if the fluid amplifying apparatusand the like can be driven by the vibratory motion of the vibratorymember, it will be possible to employ this vibration producing apparatusin a wide range of operation machines.

What is claimed is:

1. A vibration producing apparatus comprising a frame, a cylindricalspace formed in said frame, a fluid supply port communicating with saidcylindrical space, a vibratory member mounted in said cylindrical spacefor angular rotation, two shield projections disposed at positionsdiametrically opposed to each other on an outer peripheral surface ofsaid vibratory member and extending in opposite directions into slidingengagement with an inner peripheral surface of said cylindrical space,means for causing one of said shield projections to be disposed on thefluid supply port side and precluding angular rotation of said vibratorymember over a predetermined angle, fluid discharge ports adapted tomaintain communication with said cylindrical space outside the range ofmovement of the shield projections of said vibratory member, and outputports adapted to maintain communication with said cylindrical spaceoutside the range of movement of the shield projections of saidvibratory member in order to take out a fluid pressure from thecylindrical space as an output.

2. A vibration producing apparatus as defined in claim 1 wherein saidmeans for precluding angular rotation of said vibratory member over andabove a predetermined angle comprises a pair of stoppers faced toopposite sides of the other shield projection of said vibratory member.

3. A vibration producing apparatus as defined in claim 1 wherein saidfluid supply port is formed as a plurality of inclined fluid supplyports maintained in communication with the cylindrical space formed inthe frame.

4. A vibration producing apparatus as defined in claim 1 wherein saidfluid supply port is formed as a plurality of inclined fluid supplyports maintained in communication with the cylindrical space formed inthe frame, and said means for precluding angular rotation of saidvibratory member over and above a predetermined angle comprises a pairof limiters for regulating the angular rotation of the vibratory membersuch that the two inclined fluid supply ports are prevented fromcommunicating with each other through one of arcuate spaces formed bydividing the cylindrical space by the two shield projections of therotary member.

1. A vibration producing apparatus comprising a frame, a cylindricalspace formed in said frame, a fluid supply port communicating with saidcylindrical space, a vibratory member mounted in said cylindrical spacefor angular rotation, two shield projections disposed at positionsdiametrically opposed to each other on an outer peripheral surface ofsaid vibratory member and extending in opposite directions into slidingengagement with an inner peripheral surface of said cylindrical space,means for causing one of said shield projections to be disposed on thefluid supply port side and precluding angular rotation of said vibratorymember oveR a predetermined angle, fluid discharge ports adapted tomaintain communication with said cylindrical space outside the range ofmovement of the shield projections of said vibratory member, and outputports adapted to maintain communication with said cylindrical spaceoutside the range of movement of the shield projections of saidvibratory member in order to take out a fluid pressure from thecylindrical space as an output.
 2. A vibration producing apparatus asdefined in claim 1 wherein said means for precluding angular rotation ofsaid vibratory member over and above a predetermined angle comprises apair of stoppers faced to opposite sides of the other shield projectionof said vibratory member.
 3. A vibration producing apparatus as definedin claim 1 wherein said fluid supply port is formed as a plurality ofinclined fluid supply ports maintained in communication with thecylindrical space formed in the frame.
 4. A vibration producingapparatus as defined in claim 1 wherein said fluid supply port is formedas a plurality of inclined fluid supply ports maintained incommunication with the cylindrical space formed in the frame, and saidmeans for precluding angular rotation of said vibratory member over andabove a predetermined angle comprises a pair of limiters for regulatingthe angular rotation of the vibratory member such that the two inclinedfluid supply ports are prevented from communicating with each otherthrough one of arcuate spaces formed by dividing the cylindrical spaceby the two shield projections of the rotary member.